Slide fastener

ABSTRACT

THE ELEMENTS OF A SLIDE FASTENER STRINGER MADE FROM A CONTINUOUS MEANDER-SHAPED PLASTIC WIRE HAVE EACH A LONGER LEG AND A SHORTER LEG, A HEAD CONNECTING THE TWO LEGS, AND INTERMEDIATE PARTS CONNECTING EACH LEG TO AN ADJACENTLY JUXTAPOSED ELEMENT. THE LEGS AND HEAD OF EACH ELEMENT ARE ARRANGED IN A COMMON PLANE APPROXIMATELY PERPENDICULAR TO THE DIRECTION OF ELONGATION OF THE ROW FORMED BY THE ELEMENTS AND TO THE SUPPORTING FACE OF THE TAPE OR OTHER CARRIER ON WHICH THE ELEMENTS ARE MOUNTED. EACH LONGER LEG IS INTERPOSED BETWEEN A SHORTER LEG AND THE SUPPORTING TAPE FACE, AND THE INTERMEDIATE PARTS CONNECTING TWO OUTWARDLY PROJECTING SHORTER LEGS ARE PARTLY DEPRESSED INTO THE SPACE BETWEEN CORRESPONDING LONGER LEGS SO AS TO TOUCH THE CARRIER FACE. THE STITCHES WHICH FASTEN THE ELEMENTS TO THE CARRIER PASS OVER AT LEAST ONE OF THE INTERMEDIATE PARTS OF EACH ELEMENT WELL BELOW THE LEVEL OF THE TOP FACES ON THE SHORTER LEGS, AND ARE THUS WELL PROTECTED AGAINST ABRASION BY A SLIDER DURING NORMAL USE OF THE FASTENER.

E. SPECK SLIDE FASTENER June 29, 1971 2 Sheets-Sheet 1 Filed Sept. 25,1969 N l N VI'IN'I )k t *QroL glee ck [WT Kw ow MM AGE/v75 E. SPECKSLIDE FASTENER June 29, 1971 2 Sheets-Sheet 2 Filed Sept. 25, 1969 FIGSla m C Slog cl Hem 7S United States Patent US. Cl. 24-205.]. ClaimsABSTRACT OF THE DISCLOSURE The elements of a slide fastener stringermade from a continuous meander-shaped plastic wire have each a longerleg and a shorter leg, a head connecting the two legs, and intermediateparts connecting each leg to an adjacently juxtaposed element. The legsand head of each element are arranged in a common plane approximatelyperpendicular to the direction of elongation of the row formed by theelements and to the supporting face of the tape or other carrier onwhich the elements are mounted. Each longer leg is interposed between ashorter leg and the supporting tape face, and the intermediate partsconnecting two outwardly projecting shorter legs are partly depressedinto the space between corresponding longer legs so as to touch thecarrier face. The stitches Which fasten the elements to the carrier passover at least one of the intermediate parts of each element well belowthe level of the top faces on the shorter legs, and are thus wellprotected against abrasion by a slider during normal use of thefastener.

This invention relates to slide fasteners, and particularly to animprovement in a slide fastener stringer whose interlocking or fasteningelements consist of a single length of suitably shaped plastic wire.

In a fastener type which has found wide practical application, the headand legs of each fastening element extend in a common planeperpendicular to the direction of elongation of the row of fasteningelements in each stringer, and are mounted on the same supportingsurface of a carrier member such as a tape or a wider piece of fabric.The sewing stitches which fasten each element to the carrier memberextend over the exposed surface of the element and are subject to wearby a moving slider during normal use of the slide fastener.

The primary object of the invention is the provision of an improvedslide fastener of the afore-described general type in which the sewingstitches are protected against wear. In its more specific aspects, theinvention aims at shaping the fastening elements in such a manner thatthe relatively weak sewing threads are protected from the slider byprojecting parts of the relatively strong plastic wire.

According to the instant invention, the two intermediate parts of eachfastening element which connect the two leg parts thereof to respectiveadjacent fastening elements are arranged in a common plane parallel tothe supporting face of the carrier on which the elements are mounted,and are contiguously adjacent the face. The stitches which fasten therow of fastening elements to the supporting face pass over at least oneof the two intermediate parts of each element and through the carrier.They are thereby protected against snagging or wear by that leg part ofthe element which is farther from the carrier.

The exact nature of this invention as well as other objects andadvantages thereof will be readily apparent from consideration of thefollowing specification relating to the annexed drawing in which:

FIG. 1 shows a closed slide fastener of the invention in fragmentaryplan view without sewing stitches;

FIG. 2 shows the fastener of FIG. 1 in section on the line 11-11;

FIG. 3 illustrates the fastener of FIG. 1 in elevational view taken inthe direction of the arrow III in FIG. 1; and

FIGS. 4 to 7 show the device of FIG. 1 in corresponding views on asmaller scale and equipped with respective patterns of sewing stitches.

Referring initially to FIG. 1, there is shown only as much of a slidefastener as is necessary for an understanding of the invention, theslider, top and bottom stops having been omitted since they may beentirely conventional. The drawing thus shows only portions of twoidentical, pulled-up stringers, and the following description will bemainly directed to one of the stringers.

The stringer consists of a row of fastening elements made from acontinuous length of plastic wire and attached to one major face of acarrier tape 4 or 4a of textile material by sewing threads omitted fromFIG. 1.

Each element has two legs 1, 2 integrally connected by an enlargedinterlocking head 5 defining lateral pockets 6 (FIG. 2) for engagementwith an interlocking head on the other stringer. The legs 1, 2 and thehead 5 of each element are arranged in a plane perpendicular to theplane of FIG. 1, to the supporting face of the associated carrier tape4, 4a, and to the direction of elongation of the row of fastenerelements. The two legs are of different length, the longer leg 2 beinginterposed between the face of the tape 4 and the shorter leg 1. As isbest seen in FIGS. 2 and 3, the shorter legs 1 are spaced from the tapeface by one thickness of the round, plastic wire from which the fastenerelements were shaped, as will be described below.

The legs 1, 2 of each fastening element are integrally connected withcorresponding legs of the two oppositely adjacent fastening elements byintermediate parts of the length of plastic wire which, for the purposeof this description, will be assumed to belong partly to each of the twoconnected elements. Thus, intermediate parts 3 connect the longer leg 2of each element to the longer leg 2 of a following element, andintermediate parts 3 connect the shorter leg 1 to the shorter leg 1 ofthe preceding element, each pair of connected legs and the associatedintermediate parts forming an approximate U-shape, as is best seen inFIG. 1.

The U-shape constituted by the longer legs 2 and the associatedintermediate parts 3 is flat and is directly superimposed on thesupporting face of the carrier tape 4. The shorter legs 1 aresuperimposed on the associated longer legs and the intermediate parts 3which connect the legs 1 dip between two longer legs 2 to the surface ofthe tape 4, as is best seen in FIG. 3. They touch or almost touch thesupporting surface of the tape and extend in a common plane parallel tothe suporting surface with the intermediate parts 3 which connect thelonger legs 2. The shorter legs 1 thus project beyond the common levelof the legs 2 and of the intermediate parts 3, 3' away from the tape 4.

As is evident from FIGS. 4 to 7, the row of fastening elements mayreadily be sewn to the tape 4 or 4a in such a manner that the sewingthreads are protected by the projecting short legs 1 against snaggingand against wear by the slider. FIG. 4 illustrates a row of zig-zagstitches 7 which pass through the tape in the bight of each of theU-shapes mentioned above. Each stitch passes from the bight partlyformed by the longer legs 2' over the intermediate parts 3 connectingthe shorter legs where the intermediate parts are well below the levelof the shorter legs 1.

The fastener illustrated in FIG. is assembled by means of T-stitches *8having each a stem portion and a cross bar portion extending from oneend of the stem portion in two opposite directions. The several crossbar portions are longitudinally aligned and pass over the intermediateportions connecting the longer legs 2. They pass through the tapebetween the 'U-shapes formed by the longer legs 2 and the intermediateparts 3'. The stem portions extend at right angles to the length of therow of fastener elements across the most depressed portion of the joinedintermediate parts 3.

The fastener shown in FIG. 6 differs from that described above withreference to FIG. 5 in that cross bar portions of T-stitches 9 also passthrough the tape in the bights of the U-shapes formed by the longer legs2 and the intermediate parts 3'.

A straight row of chain stitches 10 passes over the intermediate parts 2only in the fastener shown in FIG. 7. In order to hold the shorter legs1 in the desired position, welds or adhesive bonds, not capable ofpictorial representation on the scale of .FIG. 7, are provided betweenthe touching surfaces of the superimposed legs 1, 2, and a fixedlyfastened connection between the legs of each fastener element may alsobe resorted to with the sewing patterns illustrated in FIGS. 4, 5 and 6.

The illustrated fastening elements are prepared in a manner partly wellknown, and partly evident from the shape of the finished elements. Roundwire of thermoplastic material, such as nylon, is first bent into a fiatmeander shape. The meander is then passed between heated rolls whichflatten the wire along 'a line parallel to but offset from thelongitudinal plane of symmetry of the meander, and the two unequalportions of the meander on the two sides of the flattening line arefolded on each other, and the intermediate portions 3 are depressed by aheated die, so as to produce the shape seen in the drawing in which theseveral fastening elements are constituted by consecutive portions of asingle continuous length of the nylon wire, respective longitudinalsections of each portion constituting the two legs, the head, and thetwo intermediate parts of the element. The shaped wire is sewn to thetape in the manner seen in FIGS. 4 to 7.

Other methods for making the fastening elements shown in the drawingwill readily suggest themselves to those skilled in the art. The plasticwire employed may be square in cross section or of any othernon-circular shape, and it need not be uniform in cross section at thetime it is bent into the meander shape, if so desired.

The basic features of the invention are also applicable to slidefasteners whose fastening elements are made from deformed wire spirals,and the necessary modifications in the illustrated fastener and in theafore-described method of preparing the same are evident so as not torequire more detailed description.

What is claimed is:

1. In a slide fastener stringer including a carrier memher having asupporting face; an elongated row of juxtaposed fastening elementsrespectively constituted by consecutive portions of a single continuouslength of plastic wire, respective longitudinal sections of each portionconstituting two leg parts, a head part, and two intermediate parts ofthe element, the intermediate parts respectively connecting the two legparts of each element to the two adjacently juxtaposed elements in saidrow, the two leg parts and the head part of each element extending in 'acommon plane substantially perpendicular to said row and to said face;and stitches securing said row of fastening elements to said face of thecarrier member in superposed relationship, the improvement whichcomprises:

(a) said two intermediate parts of each element being laterally spacedfrom each other and extending in a common plane parallel to said faceand being contiguously adjacent said face; and

(b) said stitches passing over at least one of said two intermediateparts of each element and through said carrier.

2. In a stringer as set forth in claim 1, said two intermediate partstouching said face.

3. In a stringer as set forth in claim 2, one of said two leg partsbeing interposed in said substantially perpendicular common planebetween said face and the other leg part, said leg parts havingrespective first terminal portions connected by said head part andrespective second terminal portions integral with respectiveintermediate parts, the length of said one leg part between saidterminal portions being greater than the corresponding length of saidother leg part.

4. In a stringer as set forth in claim 3, said two leg parts touchingeach other.

5. In a stringer as set forth in claim 3, the shorter leg part of eachelement being connected by associated intermediate parts to the shorterleg part of one juxtaposed element, and the longer leg part of eachelement being connected by associated intermediate parts to the longerleg part of the other juxtaposed element, whereby the connected legparts form U-shapes, the intermediate parts connecting said shorter legparts of each pair of juxtaposed elements being partly interposedbetween the longer leg parts of said pair in said parallel common plane.

6. In a stringer as set forth in claim 5, said stitches being zig-zagstitches sequentially passing over the intermediate parts connecting theshorter leg parts of said elements.

7. In a stringer as set forth in claim 5', each stitch being T-shapedand having a stern portion and a cross bar portion extending from oneend of the stem portion, said cross bar portions of the stitches beinglongitudinally aligned and passing over the U-shapes formed by theconnected longer leg parts, and the stem portions passing overrespective intermediate parts connecting two shorter leg parts.

8. In a stringer as set forth in claim 5, said stitches jointlyconstituting a row of chain stitches passing over the intermediate partsconnecting said longer leg parts.

9. In a stringer as set forth in claim 8, fastening means fixedlyfastening the two leg parts of each element to each other againstrelative movement in said substantially perpendicular common plane.

10. In a stringer as set forth in claim 1, fastening means fixedlyfastening the two leg parts of each element to each other againstrelative movement in said substantially perpendicular common plane.

References Cited UNITED STATES PATENTS 3,412,438 11/1968 Sim 24205.16CUX3,484,906 12/1969 Yoshida 24205.1CUX

FOREIGN PATENTS 222,149 6/1959 Australia 24205.l3C

BERNARD A. GELAK, Primary Examiner U.S. C1. X.R. 24205.l3, 205.16

